PyBitmessage/src/class_outgoingSynSender.py

import threading
import time
import random
import shared
import socks
import socket
import sys
import tr

from class_sendDataThread import *
from class_receiveDataThread import *

# For each stream to which we connect, several outgoingSynSender threads
# will exist and will collectively create 8 connections with peers.

class outgoingSynSender(threading.Thread):

    def __init__(self):
        threading.Thread.__init__(self)

    def setup(self, streamNumber, selfInitiatedConnections):
        self.streamNumber = streamNumber
        self.selfInitiatedConnections = selfInitiatedConnections

    def _getPeer(self):
        # If the user has specified a trusted peer then we'll only
        # ever connect to that. Otherwise we'll pick a random one from
        # the known nodes
        shared.knownNodesLock.acquire()
        if shared.trustedPeer:
            peer = shared.trustedPeer
            shared.knownNodes[self.streamNumber][peer] = time.time()
        else:
            peer, = random.sample(shared.knownNodes[self.streamNumber], 1)
        shared.knownNodesLock.release()

        return peer

    def run(self):
        while shared.safeConfigGetBoolean('bitmessagesettings', 'dontconnect'):
            time.sleep(2)
        while shared.safeConfigGetBoolean('bitmessagesettings', 'sendoutgoingconnections'):
            maximumConnections = 1 if shared.trustedPeer else 8 # maximum number of outgoing connections = 8
            while len(self.selfInitiatedConnections[self.streamNumber]) >= maximumConnections:
                time.sleep(10)
            if shared.shutdown:
                break
            random.seed()
            peer = self._getPeer()
            shared.alreadyAttemptedConnectionsListLock.acquire()
            while peer in shared.alreadyAttemptedConnectionsList or peer.host in shared.connectedHostsList:
                shared.alreadyAttemptedConnectionsListLock.release()
                # print 'choosing new sample'
                random.seed()
                peer = self._getPeer()
                time.sleep(1)
                # Clear out the shared.alreadyAttemptedConnectionsList every half
                # hour so that this program will again attempt a connection
                # to any nodes, even ones it has already tried.
                if (time.time() - shared.alreadyAttemptedConnectionsListResetTime) > 1800:
                    shared.alreadyAttemptedConnectionsList.clear()
                    shared.alreadyAttemptedConnectionsListResetTime = int(
                        time.time())
                shared.alreadyAttemptedConnectionsListLock.acquire()
            shared.alreadyAttemptedConnectionsList[peer] = 0
            shared.alreadyAttemptedConnectionsListLock.release()
            if peer.host.find(':') == -1:
                address_family = socket.AF_INET
            else:
                address_family = socket.AF_INET6
            try:
                sock = socks.socksocket(address_family, socket.SOCK_STREAM)
            except:
                """
                The line can fail on Windows systems which aren't
                64-bit compatiable:
                      File "C:\Python27\lib\socket.py", line 187, in __init__
                        _sock = _realsocket(family, type, proto)
                      error: [Errno 10047] An address incompatible with the requested protocol was used
                      
                So let us remove the offending address from our knownNodes file.
                """
                shared.knownNodesLock.acquire()
                try:
                    del shared.knownNodes[self.streamNumber][peer]
                except:
                    pass
                shared.knownNodesLock.release()
                with shared.printLock:
                    print 'deleting ', peer, 'from shared.knownNodes because it caused a socks.socksocket exception. We must not be 64-bit compatible.'
                continue
            # This option apparently avoids the TIME_WAIT state so that we
            # can rebind faster
            sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
            sock.settimeout(20)
            if shared.config.get('bitmessagesettings', 'socksproxytype') == 'none' and shared.verbose >= 2:
                with shared.printLock:
                    print 'Trying an outgoing connection to', peer

                # sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            elif shared.config.get('bitmessagesettings', 'socksproxytype') == 'SOCKS4a':
                if shared.verbose >= 2:
                    with shared.printLock:
                        print '(Using SOCKS4a) Trying an outgoing connection to', peer

                proxytype = socks.PROXY_TYPE_SOCKS4
                sockshostname = shared.config.get(
                    'bitmessagesettings', 'sockshostname')
                socksport = shared.config.getint(
                    'bitmessagesettings', 'socksport')
                rdns = True  # Do domain name lookups through the proxy; though this setting doesn't really matter since we won't be doing any domain name lookups anyway.
                if shared.config.getboolean('bitmessagesettings', 'socksauthentication'):
                    socksusername = shared.config.get(
                        'bitmessagesettings', 'socksusername')
                    sockspassword = shared.config.get(
                        'bitmessagesettings', 'sockspassword')
                    sock.setproxy(
                        proxytype, sockshostname, socksport, rdns, socksusername, sockspassword)
                else:
                    sock.setproxy(
                        proxytype, sockshostname, socksport, rdns)
            elif shared.config.get('bitmessagesettings', 'socksproxytype') == 'SOCKS5':
                if shared.verbose >= 2:
                    with shared.printLock:
                        print '(Using SOCKS5) Trying an outgoing connection to', peer

                proxytype = socks.PROXY_TYPE_SOCKS5
                sockshostname = shared.config.get(
                    'bitmessagesettings', 'sockshostname')
                socksport = shared.config.getint(
                    'bitmessagesettings', 'socksport')
                rdns = True  # Do domain name lookups through the proxy; though this setting doesn't really matter since we won't be doing any domain name lookups anyway.
                if shared.config.getboolean('bitmessagesettings', 'socksauthentication'):
                    socksusername = shared.config.get(
                        'bitmessagesettings', 'socksusername')
                    sockspassword = shared.config.get(
                        'bitmessagesettings', 'sockspassword')
                    sock.setproxy(
                        proxytype, sockshostname, socksport, rdns, socksusername, sockspassword)
                else:
                    sock.setproxy(
                        proxytype, sockshostname, socksport, rdns)

            try:
                sock.connect((peer.host, peer.port))
                rd = receiveDataThread()
                rd.daemon = True  # close the main program even if there are threads left
                someObjectsOfWhichThisRemoteNodeIsAlreadyAware = {} # This is not necessairly a complete list; we clear it from time to time to save memory.
                sendDataThreadQueue = Queue.Queue() # Used to submit information to the send data thread for this connection. 
                rd.setup(sock, 
                         peer.host, 
                         peer.port, 
                         self.streamNumber,
                         someObjectsOfWhichThisRemoteNodeIsAlreadyAware, 
                         self.selfInitiatedConnections, 
                         sendDataThreadQueue)
                rd.start()
                with shared.printLock:
                    print self, 'connected to', peer, 'during an outgoing attempt.'


                sd = sendDataThread(sendDataThreadQueue)
                sd.setup(sock, peer.host, peer.port, self.streamNumber,
                         someObjectsOfWhichThisRemoteNodeIsAlreadyAware)
                sd.start()
                sd.sendVersionMessage()

            except socks.GeneralProxyError as err:
                if shared.verbose >= 2:
                    with shared.printLock:
                        print 'Could NOT connect to', peer, 'during outgoing attempt.', err

                deletedPeer = None
                with shared.knownNodesLock:
                    """
                    It is remotely possible that peer is no longer in shared.knownNodes.
                    This could happen if two outgoingSynSender threads both try to 
                    connect to the same peer, both fail, and then both try to remove
                    it from shared.knownNodes. This is unlikely because of the
                    alreadyAttemptedConnectionsList but because we clear that list once
                    every half hour, it can happen.
                    """
                    if peer in shared.knownNodes[self.streamNumber]:
                        timeLastSeen = shared.knownNodes[self.streamNumber][peer]
                        if (int(time.time()) - timeLastSeen) > 172800 and len(shared.knownNodes[self.streamNumber]) > 1000:  # for nodes older than 48 hours old if we have more than 1000 hosts in our list, delete from the shared.knownNodes data-structure.
                            del shared.knownNodes[self.streamNumber][peer]
                            deletedPeer = peer
                if deletedPeer:
                    with shared.printLock:
                        print 'deleting', peer, 'from shared.knownNodes because it is more than 48 hours old and we could not connect to it.'

            except socks.Socks5AuthError as err:
                shared.UISignalQueue.put((
                    'updateStatusBar', tr.translateText(
                    "MainWindow", "SOCKS5 Authentication problem: %1").arg(str(err))))
            except socks.Socks5Error as err:
                pass
                print 'SOCKS5 error. (It is possible that the server wants authentication).)', str(err)
            except socks.Socks4Error as err:
                print 'Socks4Error:', err
            except socket.error as err:
                if shared.config.get('bitmessagesettings', 'socksproxytype')[0:5] == 'SOCKS':
                    print 'Bitmessage MIGHT be having trouble connecting to the SOCKS server. ' + str(err)
                else:
                    if shared.verbose >= 1:
                        with shared.printLock:
                            print 'Could NOT connect to', peer, 'during outgoing attempt.', err

                deletedPeer = None
                with shared.knownNodesLock:
                    """
                    It is remotely possible that peer is no longer in shared.knownNodes.
                    This could happen if two outgoingSynSender threads both try to 
                    connect to the same peer, both fail, and then both try to remove
                    it from shared.knownNodes. This is unlikely because of the
                    alreadyAttemptedConnectionsList but because we clear that list once
                    every half hour, it can happen.
                    """
                    if peer in shared.knownNodes[self.streamNumber]:
                        timeLastSeen = shared.knownNodes[self.streamNumber][peer]
                        if (int(time.time()) - timeLastSeen) > 172800 and len(shared.knownNodes[self.streamNumber]) > 1000:  # for nodes older than 48 hours old if we have more than 1000 hosts in our list, delete from the shared.knownNodes data-structure.
                            del shared.knownNodes[self.streamNumber][peer]
                            deletedPeer = peer
                if deletedPeer:
                    with shared.printLock:
                        print 'deleting', peer, 'from shared.knownNodes because it is more than 48 hours old and we could not connect to it.'

            except Exception as err:
                sys.stderr.write(
                    'An exception has occurred in the outgoingSynSender thread that was not caught by other exception types: ')
                import traceback
                traceback.print_exc()
            time.sleep(0.1)